construct for himself a similar instrument, and his efforts were
so far successful that at first he "saw objects three times as
near and nine times enlarged." Continuing his efforts, he
presently so improved his glass that objects were enlarged almost
a thousand times and made to appear thirty times nearer than when
seen with the naked eye. Naturally enough, Galileo turned this
fascinating instrument towards the skies, and he was almost
immediately rewarded by several startling discoveries. At the
very outset, his magnifying-glass brought to view a vast number
of stars that are invisible to the naked eye, and enabled the
observer to reach the conclusion that the hazy light of the Milky
Way is merely due to the aggregation of a vast number of tiny
stars.

Turning his telescope towards the moon, Galileo found that body
rough and earth-like in contour, its surface covered with
mountains, whose height could be approximately measured through
study of their shadows. This was disquieting, because the current
Aristotelian doctrine supposed the moon, in common with the
planets, to be a perfectly spherical, smooth body. The
metaphysical idea of a perfect universe was sure to be disturbed
by this seemingly rough workmanship of the moon. Thus far,
however, there was nothing in the observations of Galileo to bear
directly upon the Copernican theory; but when an inspection was
made of the planets the case was quite different. With the aid of
his telescope, Galileo saw that Venus, for example, passes
through phases precisely similar to those of the moon, due, of
course, to the same cause. Here, then, was demonstrative evidence
that the planets are dark bodies reflecting the light of the sun,
and an explanation was given of the fact, hitherto urged in